EP0883335A1

EP0883335A1 - Method for cultivating flower-bearing and leaf-bearing plants and tubular element to be used therewith

Info

Publication number: EP0883335A1
Application number: EP97904659A
Authority: EP
Inventors: Hermanus Johannes Van Rijn
Original assignee: VAN RIJN GROEISYSTEMEN BV; Van Rijn Hermanus Johannes
Current assignee: Van Rijn Groeisystemen BV
Priority date: 1996-02-23
Filing date: 1997-02-24
Publication date: 1998-12-16
Anticipated expiration: 2017-02-24
Also published as: WO1997030577A1; DE69713289D1; PL328464A1; EP0883335B1; NL1002439C2; AU1736997A

Abstract

A method for cultivating flower-bearing and leaf-bearing plants whose stems and branches generally grow in upward direction, wherein a number of plant parts (8), such as at least one graft and a number of shoots (9), are bent laterally as a whole, so that, adjacent the bending location, further shoots (9) originate which form the products to be cultivated, in particular cut flowers, wherein each plant is disposed in a separate tuber element (1) that is filled with cultivating soil or cultivating substrate (7), wherein each tubular element (1) is spaced from further tubular elements (1) and constructed with a length/diameter ratio such that the bent plant parts project, over the larger part of their lengths, beyond at least the top part of the circumferential wall of the tubular element (1) in a free space surrounding it, and a tubular element (1) to be used in such method.

Description

Title: Method for cultivating flower-bearing and leaf- bearing plants and tubular element to be used therewith.

The invention relates to a method for cultivating flower-bearing and leaf-bearing plants whose stems and branches generally grow in upward direction, wherein a number of plant parts, such as at least one graft and a number of shoots, are bent laterally as a whole, so that, adjacent the bending location, further shoots originate which form the products to be cultivated, in particular cut flowers, which, after having reached a desired length and development, are cut off. The invention also relates to a tubular element to be used with a cultivating method according to the invention.

In a cultivating method as referred to in the previous paragraph, the plants are preferably disposed in beds row¬ wise, and the graft (or, if present, the grafts) and a number of shoots, in general the first ground shoots and any other, unsaleable branches, are bent in the direction of and down to the bed, with the bending location being virtually at the place where the plants come out of the ground, i.e. directly above the root system. Generally, in a plant thus treated, no flowers will develop in the laterally bent plant parts, but at and adjacent the bending location shoots are formed that grow in upward direction. The bent plant parts remain leaf-bearing and hence keep assimilating, with the sugars thus formed being passed on to the newly formed shoots which, as a result, grow extremely prosperously and start forming luxuriant flowers.

The object of the invention is to further improve and optimize the above-described cultivating method.

Further objects of the invention are to improve the working circumstances for the nursery man and to create conditions for working in a more environmentally friendly manner. In accordance with the invention, this is realized in that each plant is disposed in a separate tubular element that is filled with cultivating soil or cultivating substrate, such as, inter alia, coco substance or lava granules, each tubular element being spaced from further tubular elements and constructed with a length/diameter ratio such that the bent plant parts project, over the larger part of their lengths, beyond at least the top part of the circumferential wall of the tubular element in a free space surrounding it.

Through these measures, the bent plant parts will be freely suspended in space, unlike the known method, where those plant parts are located on or directly above the bed. It has appeared that the bent, freely suspending plant parts remain leaf-bearing considerably better than plant parts that contact the bed or are located directly thereabove. By virtue of more and healthier leaves on the bent, freely suspending plant parts, the assimilation process and, accordingly, the growth process of the newly formed shoots and the flower bud development in those shoots are promoted. In addition, the assimilation process is further promoted in that the air can circulate around the freely suspending, bent plant parts in a much better and easier manner. Thus, a two-part plant with effectively separated functions is obtained, at it were: on the one hand a downwardly suspending, bent nutrient part where optimum conditions for the assimilation process are created, and on the other an upwardly extending production part where optimum conditions for growth, bud form, and harvesting are created. Hence, the result of the measures proposed in accordance with the invention is both a higher yield per plant and a highly improved quality compared with the presently known cultivating methods .

Owing to the fact that the bent plant parts are suspended in the free space, in accordance with a further embodiment of the invention, it is possible that the bent plant parts are bent through an angle greater than 90°, more in particular into a relatively steep to vertically depending position, i.e. a bending angle of 135° or more. With plant parts bent in this manner, the surface area occupied by a plant in top plan view can be utilized more profitably. It is then also promoted that the plant can develop optimally and hence grow larger and more massive. In this connection, in accordance with a further embodiment of the invention, it is further preferred that a number of tubular elements be spaced apart so that the bent plant parts of one plant can hardly touch, if at all, those of another plant. Thus, all the plants are not only conveniently grouped and can be surveyed and treated individually, but, if necessary, each plant can also be removed and replaced by another without influencing the other plants .

Through the use of the tubular elements, which preferably have a length at least equal to the maximum length of the bent plant parts, the plant is as it were elevated. This has the additional advantage that the plant thereby automatically takes up a higher position and hence becomes accessible to the nursery man without stooping low, in other words: it assumes a more proper working height. Thus, not only can the plant parts to be harvested be reached in a quick and simple manner by elevating the plant and bending the other plant parts away and downwards, but the plant is also arranged more conveniently for the other operations to be performed.

The tubular element can be disposed on or partially in a bed, with the length of the tubular element above the bed being so that the downwardly bent plant parts remain clear of the bed. However, in accordance with a further embodiment of the invention, it is preferred that each tubular element has its bottom side provided with a closure and that, in or adjacent that closure, drain openings be provided, with a number of such tubular elements being disposed above a water discharge gutter. Through these measures, a number of additional, yet significant advantages can be realized. A water or waste water surplus can be centrally collected and discharged in a particularly environmentally friendly manner, so that the pollutions present therein can be separated efficiently, which considerably increases the guarantee that the harmful substances do not end up in the environment. Further, by disposing the tubular elements above the gutter, and more in particular by creating an open space between the closure of the tubular element with its discharge openings and the bottom of the gutter, a root stop can effectively be obtained, because roots which from a dark, moist environment end up in a light, relatively dry environment, stop growing. In this connection, it is additionally observed that the drain openings prevent root rot. In this manner, a healthy lower end of the root system can be obtained, which remains entirely within the tubular element. This last has the further advantage that the root system of one plant remains entirely out of contact with that of another plant, so that contact infections between the plants are prevented. Further, the closing of the tubular element and its arrangement above a gutter, which may also have the form of a discharge pipe or a container or bucket, optionally provided with a drain possibility, further has the advantage that a or a number of plants can readily be removed and replaced by new and/or other plants, for instance in the case of diseased plants, or improperly or irregularly growing plants.

The closing of the tubular element can be effected by squeezing that element close at the bottom side thereof; however, the provision of a bottom plate will be preferred. In order to dispose such elements above a gutter, in accordance with a further embodiment of the invention, it is preferred that each tubular element be provided with foot means and that a number of such tubular elements be disposed on a discharge gutter so as to supported thereby. If the foot means extend beyond the bottom side of the tubular element, the enlargement of the open space under the tubular element further improves the occurrence of the root-stop effect and the advantages obtained thereby, as discussed hereinabove.

In accordance with a further embodiment of the invention, it is also possible that a number of tubular elements are suspended above a discharge gutter. In this connection, for instance heating pipes could serve as suspension means.

The invention further relates to a tubular element to be used with a method as discussed hereinabove. The tubular element can be manufactured from any suitable material of a certain inherent stiffness, for instance from plastic, ceramics, metal, concrete, glass, and the like. Further, the tubular form can have any desired cross section, which can moreover vary over the height of the tubular element, for instance circular at one end and polygonal at the other end. As mentioned, it is particularly preferred that the bent plant parts do not contact the bed, any different type of bottom or a discharge gutter, in order that the bent plant parts are freely suspended as much as possible. To promote this effect, hence to keep as much foliage as possible, in the healthiest possible condition, on the bent plant parts, it is further preferred that those plant parts be released from the tubular element as quickly as possible, i.e. the circumference of the tubular element in the upper area is kept as small as possible. Starting from the above, in accordance with the invention, it is preferred that the length of the tubular element be at least twice the transverse dimension of the tubular element adjacent its upper end, or the smallest transverse dimension if the tubular element has an elongated cross section. Considering the manner of growth of most plants, in accordance with a further preferred embodiment of the invention, it is preferred that the tubular element has a circular cross section at least in its upper area. When the upper edge area of the tubular element is kept as small as possible, it will be possible that the top face of that element is virtually entirely occupied by plant parts coming out of the ground or another nutrient substrate. Hence, in accordance with a further embodiment of the invention, it is preferred that in the upper end area of the tubular element, one or a number of irrigation and soil aeration holes be provided. Thus, the watering and feeding of a plant can be controlled in an optimum manner.

To prevent damages to the bent plant parts, it is further preferred that the upper edge of the tubular element be of a rounded or beaded design. As mentioned above, the tubular element can be stuck into a bed. This can also be a locally limited bed, i.e. the tubular element extends over a part of its length into a pot-shaped container filled with cultivating soil or another nutrient substrate, while it is then preferably provided that means be present for securing the tubular element in the pot-shaped container. The securing means can be constructed in many ways . It is for instance possible that the securing means consist of ribs attached to the outside of the tubular element and/or the inside of the pot-shaped container. Another possibility is that the securing means consist of a cover to be fixed on the pot-shaped container, which cover is provided with pass and/or securing means for the tubular element. It is also possible that the tubular element is disposed on that bed or disposed above that bed, a discharge gutter or another bottom. When the tubular element is being stuck into the bed, it may be open at its bottom side. However, it is also possible, and for arrangement above the bed it is preferred, that the tubular element has its lower end provided with a closure. This closure can be realized in many ways. For instance, the lower end of the tubular element can be deformed into a more or less closing form. Likewise, it is possible to close the bottom side with a plate-shaped or cover-shaped part which may or may not be detachable. In the case where the tubular element has its lower end provided with a closure, it is preferred, inter alia to prevent root rot, that drain openings be provided in or adjacent the lower end of the tubular element. Depending on the size of the drain openings, soil and/or root turning means can further be provided in the tubular element, if so desired.

In a tubular element of a cylindrical shape, a relatively small upper end of the tubular element also means a relatively small lower end. This could, however, cause stabilization problems. To be able to overcome such problems, in accordance with a further embodiment of the invention, it is proposed that the outside of the tubular element be provided with stabilization means, such as, for instance, fin-shaped projecting parts, which may have many shapes. For sticking a tubular element into a bed, those stabilization means can for instance have the shape of vertically arranged, triangular fins, with an angular point forming the lower end of the stabilization means . It is thus provided that the tubular element can be pressed or driven into the bed relatively easily, while a stable, upright tubular element is nevertheless obtained.

If the tubular element is to be disposed on or above the bed, a discharge gutter or another bottom, in accordance with a further embodiment of the invention, it is preferred that the stabilization means comprise means forming a foot. These means, too, can have the shape of triangular, fin- shaped projections, although for obtaining a bottom support face, the point of the triangle is now upwardly directed. Further, the fins can be connected to a bottom support plate, while it is of course also possible that a bottom support plate is present that is larger relative to the tubular element and without fin-shaped projections. When it is for instance of concrete construction, that bottom- support plate may form part of a block.

To promote the root-stop effect and the controlled drain and water discharge possibilities, in accordance with a further embodiment of the invention, it is preferred that the means forming a foot extend beyond the lower end of the tubular element. To obtain a stably standing tubular element, it is also possible to provide the lower end of the tubular element with a larger cross section than the upper end, which should be kept as small as possible. This can for instance be realized by giving the tubular element a stepped construction. In accordance with a further embodiment of the invention, however, it is preferred that the tubular element be of conical design, diverging from top to bottom. For particular plants, this embodiment further has the advantage that in spite of a small top face, a large volume is available for the root system of the plant. If, in particular cases, it were necessary to remove the plant from the tubular element, that tubular element can be of divisible design, for instance by being composed of two shell halves. Of course, in these cases, a tubular element which is of conical design tapering from top to bottom can also be opted for.

A particular preference is had for an embodiment from which, in practice, optimum results are expected in various respects and wherein the tubular element comprises a conical tube part diverging from top to bottom and a cover-shaped bottom part, wherein the tube part is provided, in its lower area, with a number of circumferentially distributed ribs extending substantially vertically and projecting under the lower edge of the tube part, and, at its lower edge, with a number of circumferentially distributed flange parts extending substantially horizontally and projecting outwards from the outer surface of the tube part, and wherein the bottom part comprises a plate-shaped part and a circumferential edge extending upwards from that part, which circumferential edge is its free upper edge provided with a number of circumferentially distributed projections extending substantially horizontally and projecting inwards from the inner surface of the circumferential edge, the arrangement being such that the bottom part can be fixedly clamped on the tube part through cooperation of the flange parts and the projections, with the ribs resting against the plate-shaped part, so that, when the bottom part is clamped on the tube part, an open gap remains between tube part and bottom part. Through these measures, a tubular element can be obtained that can be manufactured in a relatively simple manner and that has optimal possibilities for bending plant parts through more than 90°, wherein that tubular element is originally particularly stable and is easy to displace and group or regroup, while there is also provided a root growth stop. If a number of circumferentially distributed openings are provided in the bottom part, at the transition between the plate-shaped part and the circumferential edge, a suitable drainage is readily provided. In this connection, the manufacture of the bottom part, which is effected through injection molding, can be simplified if the openings are provided below the projections. In that case, the inwardly extending projections do not cause any relief problems during the manufacture of the bottom part in an injection mold. To realize the clamping connection between tube part and bottom part in a quick, simple and reliable manner, it is further proposed that the flange parts be provided with a locating edge part, a clamping part and a stop part.

If the tube part further is provided, in its upper area, with valve means which form part of the tube part and can be pivotally pressed inwards or outwards relative to the circumferential wall thereof, there is provided a possibility of providing, if so desired, a watering possibility below the top face, which can for instance be entirely occupied by a plant.

To prevent a number of tube parts from wedging rigidly in one another during transport or storage, it is preferred that the tube part be internally provided, in its upper area, with a number of circumferentially distributed ribs which extend substantially radially and vertically and which are dimensioned so that when a number of tubular elements are nested, the upper edge of a subjacent tubular element butts against the bottom sides of the ribs of a superjacent tubular element before the tubular elements can clampingy wedge in one another.

The ability to displace the tubular element in a simple and quick manner can further be promoted if the tube part has its outside provided with handgrip means.

Hereinafter, the method according to the invention and the tubular elements to be used therewith will be specified, with reference to exemplary embodiments shown in the accompanying drawings. In these drawings:

Fig. 1 shows a first embodiment of a tubular element with a plant cultivated therein according to the invention;

Fig. 2 shows a second embodiment of a tubular element according to the invention, disposed in a receptacle; Fig. 3 shows a section taken on line III-III in Fig. 2;

Fig. 4 shows a third embodiment of a tubular element according to the invention, disposed in a container having a cover;

Fig. 5 shows a fourth embodiment of a tubular element according to the invention, suspended above a discharge gutter;

Fig. 6 shows a fifth embodiment of a tubular element according to the invention, to be disposed in a container;

Fig. 7 shows a sixth embodiment of a tubular element according to the invention;

Fig. 8 shows a seventh embodiment of a tubular element according to the invention;

Fig. 9 shows an eighth embodiment of a tubular element according to the invention; Fig. 10 shows a ninth embodiment of a tubular element according to the invention, disposed on a discharge gutter;

Fig. 11 shows a tenth embodiment of a tubular element according to the invention, disposed on a discharge gutter;

Fig. 12 shows, partly in elevation and partly in section, an eleventh embodiment of a tubular element according to the invention; Fig. 13 shows a section taken on the line A-A in Fig. 12; and

Fig. 14 shows in cross section a detail of the eleventh embodiment, to an enlarged scale. Fig. 1 shows a tubular element 1 consisting of a cylindrical sleeve part having a constant circular cross section. The sleeve part 1 is at its bottom side closed by a cover 2 having four projections 3 that serve as legs, so that the cover 2 and, accordingly, the tubular element 1, are substantially free from a positioning face not shown in Fig. 1. The cover 2 is further provided with drain openings 4. Similar drain openings 5 are provided in the tubular element 1. Further, the tubular element 1 is open at the top and provided, at that location, with a rounded upper edge 6. The tubular element 1 is virtually entirely filled with cultivating soil 7 or another cultivating substrate, such as, for instance, cocos substance or lava granules.

The tubular element 1 and the cover 2 are manufactured from plastic. However, this material could as well have been any other suitable material, such as concrete, ceramics, glass, metal, and the like. It is presently observed that the same applies to the embodiments of the tubular element to be discussed hereinbelow. Likewise, all those embodiments can have, apart from the circular form mentioned, any desired cross section, such as square, rectangular, polygonal, oval, etc.

Disposed in the tubular element 1 filled with cultivating soil 7 is a plant whose plant parts 8, such as a graft, a first ground shoot and, possibly, an unsaleable branch, are bent away aside and downwards. The diameter of the tubular element 1 is chosen so that the bent plant parts 8 extend outside the rounded upper edge 6 and hence into the free space around the tubular element 1 as quickly as possible. Thus, those bent plant parts 8 will be optimally leaf-bearing, so that extremely advantageous assimilation conditions are created, which are moreover further promoted in that the air can surround and pass over the leaves on all sides. To keep these conditions optimal, the height of the tubular element 1 should be chosen so that the bent plant parts 8 always remain suspended in the free space, i.e. they hardly contact, if at all, the positioning face of the tubular element 1. The sugars produced during the assimilation process are passed on to the newly formed shoots 9, formed near the location where the plant comes out of the cultivating soil, i.e. substantially from the heart of the plant and the first bending area of the bent plant parts 8. In this manner, optimum growth conditions are created for the shoots 9 growing straight upwards, so that these shoots will grow relatively quickly and will be luxuriantly flower-bearing. The thus cultivated cut flowers 10 are harvested and sold at the desired point of time. Fig. 2 shows a tubular element 11 whose cross section increases in downward direction. Thus, with a minimum top surface and hence maximally freely suspending, bent plant parts, a relatively large root-growth volume can be obtained. If the plant should be able to be removed from the tubular element 11 without damages, the tubular element 11 can be manufactured from two shells 11a and lib, each having a flanged edge at the interface, while two adjoining flanged edges can be fixed one against the other by means of a clamping element 12, as shown in Fig. 3. Further, the tubular element 11 has its upper edge provided with a beaded edge 13, preventing damages to the bent plant parts. At the bottom side, the tubular element 11 is closed by a bottom 14 having drain openings 15. To enable the tubular element 11 to be detached from the plant, the bottom 14 is detachably connected to the tubular element 11 in a manner not shown. This tubular element 11 further has its outside provided with a number of projecting fins 16 projecting under the bottom 14 through a certain distance. In this manner, legs are provided that keep the bottom 14 free from the positioning face, which in this embodiment consists of the bottom of a container 17, which, if so desired, can be connected to a drain system. Fig. 4 shows a tubular element 21 disposed in a pot- shaped container 22 which can at least partly be filled with cultivating soil and which is closed by a cover 23 provided with soil aeration and soil irrigation holes 24. The tubular element 21 rests on the bottom of the pot-shaped container 22 and is further held in position by a central opening 25 in the cover 24, which opening 25 is adjusted to the section of the tubular element 21. At its lower-end area, the tubular element 21 is further provided with slot-shaped openings 26 whereby the interior of the tubular element 21 is in connection with the interior of the pot-shaped container 22. These slot-shaped openings 26 serve as root holes and can also be of a different design, for instance round. Fig. 5 shows a tubular element 31 having a configuration which slightly tapers from its upper edge in downward direction. The lower end of the tubular element 31 is inwardly deformed into a nozzle-shaped end 32 extending into an opening 33 of a drain pipe 34. In its upper area, the tubular element 31 comprises a ring 35 extending around its circumference and serving to attach thereto a wire 36 for bringing the tubular element 31 in suspended position, as the wire 36 passes over, for instance, heating pipes 37. Fig. 6 shows a tubular element 41 having a flanged upper edge 42 above a pot-shaped container 43, internally provided with cross-shaped ribs 44 wherein recesses 45 are provided for receiving the tubular element 41. The recesses 45 are dimensioned so that a tubular element 41 inserted therein assumes a stable position. Further, recesses 46 are provided in the fins 44, so that the four compartments of the pot-shaped container 43 are in mutual contact. If so desired, the pot-shaped container 43 can further comprise drain provisions.

Fig. 7 shows a tubular element 51 having a beaded upper edge 52, which can be disposed directly in or on a bed of cultivating soil or another cultivating substrate. From the upper edge 52, the tubular element 51 has a tapering shape for realizing a smallest possible top face. This last may mean that a plant occupies the top face completely or almost completely. For irrigating and feeding the plant, use can then be made of a nozzle 53 located directly below the beaded upper edge 52. If the tubular element 51 is partly stuck into a bed, root hole bores can further be provided in that part sticking into the bed, if so desired.

Fig. 8 shows a tubular element 61 having a flanged upper edge 62 and having its lower end area provided with quadrangular stabilization fins 63 whereby the tubular element 61 can be stably positioned on a bed or another surface.

Fig. 9 shows a tubular element 71 having a flanged upper edge 72 and having its lower end area provided with triangular stabilization fins 73, whose points are downwardly directed. This renders the tubular element 71 particularly suitable for being stuck or driven into a bed of cultivating soil, with the fins 73 readily penetrating into the soil and providing that the tubular element 71 remains in position in a stable manner. Further provided between the fins 73 are a number of root holes 74.

Fig. 10 shows a tubular element 81, secured in a concrete base 82 supported by two L-shaped sections, which, in turn, rest on a bottom plate 84. As Fig. 10 demonstrates, the parts 83 and 84 together form a discharge gutter, with the bottom of the base 82 that supports the tubular element 81 being located at a distance above the top face of the bottom plate 84. Although not shown, it will be appreciated that the tubular element 81 and the base 82 are provided with openings through which waste water can find its way into the discharge gutter.

Fig. 11 shows a tubular element 91 having its lower area provided with supporting ribs 92. The lower ends of the tubular element 91 and the ribs 92 are in the same plane and connect at that location to a bottom plate 93 resting on the upright side edges of a U-shaped discharge gutter 94. For draining purposes, the bottom plate 93 is provided, in the area closing the tubular element 91, with openings, not shown in the drawing. In the case of a circular or square cross section of the tubular element 91, to obtain a maximally stable positioning of the tubular element 91, the bottom plate 93 will have a square shape of such dimensions that two opposite side edges rest throughout their lengths on the upper edges of the discharge gutter 94.

Figs. 12-14 show an embodiment which is expected to yield optimum results, in practice. The tubular element is composed of a relatively thin-walled, hollow tube part 101 having a conical shape diverging from top to bottom, and a cover-shaped bottom part 102.

The tube part 101 has a rounded upper edge 103, outwardly slightly thickened. Further, the tube part 101 comprises in its upper area six radially inwardly extending ribs 104, which are evenly distributed over the inner circumference and which all have the shape of a right-angled triangle, wherein one cathetus extends vertically and has the end opposite the right angle connecting to the inside of the upper edge 103, and the other cathetus points radially inwards . Also provided in the upper area of the tube part is a valve member 105, shown to an enlarged scale, in cross section, in Fig. 14. The valve member 15 is formed from the wall material of the tube part 101 through the provision of a substantially U-shaped cut, the lower part of the cut- loose U-shaped part having a thickness substantially equal to that of the wall of the tube part 101 and the upper part becoming thinner in upward direction, so that the cut-loose U-shaped part can pivot about its upper edge, as indicated in Fig. 14. At the location of the U-shaped cut, the wall of the tube part 101 is reinforced by means of a U-shaped rib 106. At its lower end, the tube part 101 comprises a cylindrical edge 107 having on its lower end eight flanges 108, evenly distributed over the circumference so as to extend outwards substantially horizontally. Each flange 108 comprises a locating edge part 108a, a clamping part 108b and a stop part 108c. Further, in the lower area of the tube part 101, six radially inwardly extending ribs 109 are provided on the inner wall thereof, which ribs extend beyond the lower end of the cylindrical edge 107 and the bottom face of the flanges 108 to form a number of legs which keep the lower circumferential edge of the tube part 101 spaced from a positioning face. Finally, the tube part 101 further has its outer surface provided with two handgrips 110.

The bottom part 102 substantially consists of a cover- shaped part comprising a circular bottom plate 111 and a circumferential edge 112 perpendicular thereto, along the top side of which eight inwardly extending projections 113 are provided, evenly distributed over the circumference. The inside diameter of the circumferential edge 112 and the free distance between two projections 113 is chosen so that when the tube part 101 is disposed on the bottom part 102, the eight flanges 108 of the tube part 101 can each move downwards between two projections 113 until the lower ends of the ribs 109 contact the bottom plate 111, the respective dimensions being chosen so that the bottom sides of the projections 113 are located slightly below the top faces of the clamping parts 108b. By rotating the bottom part 102 relative to the tube part 101 in a suitable manner, clockwise in Fig. 13, the bottom sides of the projections 113 will run against the top faces of the locating edge parts 108a, whereupon further rotation of the bottom part 101 until the projections 113 butt against the stop parts 108c through cooperation of the clamping parts 108b and the projections 113 results in a clamping connection between the tube part 101 and the bottom part 102, with an open passage remaining between the two parts, which open passage hence acts as root-growth stop. Further, at the location of each projection 113, a water discharge opening 114 is present in the bottom part 102. The provision of those openings 114 at the location of the projections 114 facilitates the manufacture of the bottom part 102, in terms of injection molding engineering. For reasons of strength and stiffness, the central area of the bottom plate 111 is depressed inwardly, and at the location of that depression, a radial rib 115 is provided.

After the foregoing, the functions of the flanges 108, the ribs 109 and the projections 113 will be understood. The same will apply to the handgrips 110. The clamping member 105, of which several may be present, if necessary, can be used for an irrigation provision. Finally, the ribs 104 prevent clamping parts 101 from wedging tightly in one another when a number of those tube parts 101 are nested, for instance during transport or storage. Further, for nesting a number of tube parts 101, the handgrips 110 and the ribs 109 can be suitably dimensioned.

It is readily understood that within the framework of the invention as laid down in the appended claims, many further modifications and variations are possible. For instance, in the embodiments wherein tubular elements in the form of straight cylinders are shown, tapering or diverging tubular forms can be used as well, and the other way round. Non-straight tubular elements may also have a bent or stepped, staggered surface. The optimal form can in each case be determined on the basis of the manner of growth of the plant and root system. Further, if necessary, the tubular elements can be provided with a light-reflecting layer whenever this could further promote the growth process.

Claims

CONCLUSIES

1. A method for cultivating flower-bearing and leaf- bearing plants whose ste s and branches generally grow in upward direction, wherein a number of plant parts, such as at least one graft and a number of shoots, are bent laterally as a whole, so that, adjacent the bending location, further shoots originate which form the products to be cultivated, in particular cut flowers, which, after having reached a desired length and development, are cut off, characterized in that each plant is disposed in a separate tubular element that is filled with cultivating soil or cultivating substrate, such as, inter alia, coco substance or lava granules, each tubular element being spaced from further tubular elements and constructed with a length/diameter ratio such that the bent plant parts project, over the larger part of their lengths, beyond at least the top part of the circumferential wall of the tubular element in a free space surrounding it.

2. A method according to claim 1, characterized in that the bent plant parts are bent through an angle greater than 90°.

3. A method according to claim 1 or 2, characterized in that a number of tubular elements are spaced apart so that the bent plant parts of one plant hardly touch, if at all, those of another plant.

4. A method according to any one of the preceding claims, characterized in that each tubular element has its bottom side provided with a closure and that, in or adjacent said closure, drain openings are provided, with a number of such tubular elements being disposed above a water discharge gutter.

5. A method according to any one of the preceding claims, characterized in that each tubular element is provided with foot means and that a number of such tubular elements are disposed on a discharge gutter so as to supported thereby.

6. A method according to any one of claims 1-4, characterized in that a number of tubular elements are suspended above a discharge gutter.

7. A tubular element to be used in a method for cultivating flower-bearing and leaf-bearing plants according to any one of the preceding claims, characterized in that the length of the tubular element is at least twice the transverse dimension of the tubular element adjacent its upper end, or the smallest transverse dimension if the tubular element has an elongated cross section.

8. A tubular element according to claim 7, characterized in that it has a circular cross section at least in its upper area.

9 A tubular element according to claim 7 or 8, characterized in that in the upper end area thereof, one or a number of irrigation and soil aeration holes are provided.

10. A tubular element according to any one of claims 7-9, characterized in that its upper edge is of a rounded or beaded design.

11. A tubular element according to any one of claims 7-10, characterized in that the tubular element extends over a part of its length into a pot-shaped container filled with cultivating soil or another nutrient substrate.

12. A tubular element according to claim 11, characterized in that means are present for securing the tubular element in the pot-shaped container.

13. A tubular element according to claim 12, characterized in that the securing means consist of ribs attached to the outside of the tubular element and/or the inside of the pot- shaped container.

14. A tubular element according to claim 12 or 13, characterized in that the securing means consist of a cover to be fixed on the pot-shaped container, said cover being provided with pass and/or securing means for the tubular element.

15. A tubular element according to any one of claims 7-14, characterized in that the tubular element is provided with a closure at its lower end.

16. A tubular element according to any one of claims 7-15, characterized in that drain openings are provided in or adjacent the lower end of the tubular element.

17. A tubular element according to any one of claims 7-16, characterized in that the outside of the tubular element is provided with stabilization means.

18. A tubular element according to claim 17, characterized in that the stabilization means comprise means forming a foot.

19. A tubular element according to claim 18, characterized in that the means forming a foot extend beyond the lower end of the tubular element.

20. A tubular element according to any one of claims 7-19, characterized in that the tubular element is of conical design, diverging from top to bottom.

21. A tubular element according to claim 7, characterized in that a conical tube part is provided, diverging from top to bottom, and a cover-shaped bottom part, wherein the tube part is provided, in its lower area, with a number of circumferentially distributed ribs extending substantially vertically and projecting beyond the lower edge of the tube part, and, at its lower edge, with a number of circumferentially distributed flange parts extending substantially horizontally and projecting outwards from the outer surface of the tube part, and wherein the bottom part comprises a plate-shaped part and a circumferential edge extending upwards from that part, which circumferential edge is its free upper edge provided with a number of circumferentially distributed projections extending substantially horizontally and projecting inwards from the inner surface of the circumferential edge, the arrangement being such that the bottom part can be fixedly clamped on the tube part through cooperation of the flange parts and the projections, with the ribs resting against the plate- shaped part, so that, when the bottom part is clamped on the tube part, an open gap remains between tube part and bottom part.

22. A tubular element according to claim 21, characterized in that a number of circumferentially distributed openings are provided in the bottom part, at the transition between the plate-shaped part and the circumferential edge.

23. A tubular element according to claim 22, characterized in that the openings are provided below the projections.

24. A tubular element according to claim 21, characterized in that the flange parts are provided with a locating edge part, a clamping part and a stop part.

25. A tubular element according to claim 21, characterized in that the tube part is provided, in its upper area, with valve means which form part of the tube part and can be pivotally pressed inwards or outwards relative to the circumferential wall thereof.

26. A tubular element according to claim 21, characterized in that the tube part is internally provided, in its upper area, with a number of circumferentially distributed ribs which extend substantially radially and vertically and which are dimensioned so that when a number of tubular elements are nested, the upper edge of a subjacent tubular element butts against the bottom sides of the ribs of a superjacent tubular element before the tubular elements can clampingy wedge in one another.

27. A tubular element according to claim 26, characterized in that the tube part has its outside provided with handgrip means.